The results of the UK parliamentary probe into phone hacking illustrate the profound difficulties that would result in Australia if politics were allowed to sour media regulation, which will happen if Australia follows the Convergence Review’s recommendations.

Released last week, the Convergence Review recommends that media mergers and takeovers be subject to a public interest test, which resembles the vague “public interest” and “suitability” tests used in the United Kingdom.

There is no doubt that News Corporation is guilty of egregious wrongdoing in phone hacking. Company employees broke the law and grossly invaded privacy. To that must be added this newspaper’s revelations that a News subsidiary fostered the hacking of rival services in the early days of the pay television industry.

These issues raise legitimate concerns about the corporate governance of News, with the parliamentary committee unanimously finding that Rupert Murdoch and his son James Murdoch had shown “wilful blindness” to what was going on in their company. But the unanimity degenerated into a straight party line split when it came to the question of declaring that Mr Murdoch is not a “fit and proper person” to lead a major corporation. In making this finding, the sole Liberal Democrat MP of the committee sided with the five Labour members, to be opposed by the five Conservative members.

This split along left-conservative lines would seem to have been driven by the political stance of News’s media outlets. Few would doubt that News runs a centre-right political agenda, but so what? The Guardian newspaper and the BBC run a centre-left agenda, much like the ABC does here in Australia, and there is no evidence that Sky News in the UK is wildly biased or partisan.

Politicians may find the thought of regulating news in the public interest an enticing one. But the reality is that, as the results of the UK inquiry show, these attempts will quickly degenerate into efforts to control the media. This control will be imposed on media outlets struggling with a market that is being fragmented by rapidly changing technology.

By suggesting that Australia adopt UK-style tests, the Convergence Review is opening the door to political control of the media, and to restrictions on freedom of speech that is a foundation of a robust democracy. We have only to look at what has happened in Australia to realise that these concerns are substantial. A minority Prime Minister has used the phone hacking scandal in the UK as an excuse to hold a media inquiry run by a politically naive former judge and various left-liberal academics. But the inquiry has been rigged from the start to threaten legislation in retaliation for the media’s vigorous but legitimate coverage of the government’s failings.

The Convergence Review, takes the UK efforts a step further by recommending calling all media companies “content service enterprises” and subjecting them to UK-style tests when it comes to takeovers, although the “suitability” and “public interest” tests in the UK apply to broadcast media, not newspapers. But to restrict potential media owners to those judged to be in the public interest by some arbitrary panel would limit the pool of capital available for media investment that would help neither public debate nor news gathering.

Not even English lawyers know what constitutes public interest or what makes a person fit and proper. These concepts are whatever the regulator, Ofcom, thinks they should be, and that is a recipe for political interference.